diff options
author | Paul E. McKenney <paulmck@linux.vnet.ibm.com> | 2010-04-13 14:19:23 -0700 |
---|---|---|
committer | Paul E. McKenney <paulmck@linux.vnet.ibm.com> | 2010-05-10 11:08:34 -0700 |
commit | 26845c2860cebebe6ce2d9d01ae3cb3db84b7e29 (patch) | |
tree | 83849948ea7bffb5e87eecc17a7275e357740632 /kernel | |
parent | c68de2097a8799549a3c3bf27cbfeea24a604284 (diff) |
rcu: print boot-time console messages if RCU configs out of ordinary
Print boot-time messages if tracing is enabled, if fanout is set
to non-default values, if exact fanout is specified, if accelerated
dyntick-idle grace periods have been enabled, if RCU-lockdep is enabled,
if rcutorture has been boot-time enabled, if the CPU stall detector has
been disabled, or if four-level hierarchy has been enabled.
This is all for TREE_RCU and TREE_PREEMPT_RCU. TINY_RCU will be handled
separately, if at all.
Suggested-by: Josh Triplett <josh@joshtriplett.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Diffstat (limited to 'kernel')
-rw-r--r-- | kernel/rcutree.c | 6 | ||||
-rw-r--r-- | kernel/rcutree_plugin.h | 44 |
2 files changed, 42 insertions, 8 deletions
diff --git a/kernel/rcutree.c b/kernel/rcutree.c index 595fb83e9b7d..ec6196fcd1fa 100644 --- a/kernel/rcutree.c +++ b/kernel/rcutree.c @@ -1938,12 +1938,6 @@ void __init rcu_init(void) int cpu; rcu_bootup_announce(); -#ifdef CONFIG_RCU_CPU_STALL_DETECTOR - printk(KERN_INFO "RCU-based detection of stalled CPUs is enabled.\n"); -#endif /* #ifdef CONFIG_RCU_CPU_STALL_DETECTOR */ -#if NUM_RCU_LVL_4 != 0 - printk(KERN_INFO "Experimental four-level hierarchy is enabled.\n"); -#endif /* #if NUM_RCU_LVL_4 != 0 */ RCU_INIT_FLAVOR(&rcu_sched_state, rcu_sched_data); RCU_INIT_FLAVOR(&rcu_bh_state, rcu_bh_data); __rcu_init_preempt(); diff --git a/kernel/rcutree_plugin.h b/kernel/rcutree_plugin.h index f9bc83a047da..0ae2339ab04d 100644 --- a/kernel/rcutree_plugin.h +++ b/kernel/rcutree_plugin.h @@ -26,6 +26,45 @@ #include <linux/delay.h> +/* + * Check the RCU kernel configuration parameters and print informative + * messages about anything out of the ordinary. If you like #ifdef, you + * will love this function. + */ +static void __init rcu_bootup_announce_oddness(void) +{ +#ifdef CONFIG_RCU_TRACE + printk(KERN_INFO "\tRCU debugfs-based tracing is enabled.\n"); +#endif +#if (defined(CONFIG_64BIT) && CONFIG_RCU_FANOUT != 64) || (!defined(CONFIG_64BIT) && CONFIG_RCU_FANOUT != 32) + printk(KERN_INFO "\tCONFIG_RCU_FANOUT set to non-default value of %d\n", + CONFIG_RCU_FANOUT); +#endif +#ifdef CONFIG_RCU_FANOUT_EXACT + printk(KERN_INFO "\tHierarchical RCU autobalancing is disabled.\n"); +#endif +#ifdef CONFIG_RCU_FAST_NO_HZ + printk(KERN_INFO + "\tRCU dyntick-idle grace-period acceleration is enabled.\n"); +#endif +#ifdef CONFIG_PROVE_RCU + printk(KERN_INFO "\tRCU lockdep checking is enabled.\n"); +#endif +#ifdef CONFIG_RCU_TORTURE_TEST_RUNNABLE + printk(KERN_INFO "\tRCU torture testing starts during boot.\n"); +#endif +#ifndef CONFIG_RCU_CPU_STALL_DETECTOR + printk(KERN_INFO + "\tRCU-based detection of stalled CPUs is disabled.\n"); +#endif +#ifndef CONFIG_RCU_CPU_STALL_VERBOSE + printk(KERN_INFO "\tVerbose stalled-CPUs detection is disabled.\n"); +#endif +#if NUM_RCU_LVL_4 != 0 + printk(KERN_INFO "\tExperimental four-level hierarchy is enabled.\n"); +#endif +} + #ifdef CONFIG_TREE_PREEMPT_RCU struct rcu_state rcu_preempt_state = RCU_STATE_INITIALIZER(rcu_preempt_state); @@ -38,8 +77,8 @@ static int rcu_preempted_readers_exp(struct rcu_node *rnp); */ static void __init rcu_bootup_announce(void) { - printk(KERN_INFO - "Experimental preemptable hierarchical RCU implementation.\n"); + printk(KERN_INFO "Preemptable hierarchical RCU implementation.\n"); + rcu_bootup_announce_oddness(); } /* @@ -757,6 +796,7 @@ void exit_rcu(void) static void __init rcu_bootup_announce(void) { printk(KERN_INFO "Hierarchical RCU implementation.\n"); + rcu_bootup_announce_oddness(); } /* |